State Key Laboratory of Oncology in Southern China, Department of Radiation Oncology, Sun Yat-Sen University Cancer Center, Guangzhou, Guangdong, People's Republic of China ; Guangdong Esophageal Cancer Research Institute, Guangzhou, Guangdong, People's Republic of China.
PLoS One. 2013 Sep 9;8(9):e73446. doi: 10.1371/journal.pone.0073446. eCollection 2013.
The objective of this study was to investigate the number of metastatic lymph nodes (pN) and the metastatic lymph node ratio (MLR) on the post-surgical prognosis of Chinese patients with esophageal cancer (EC) and lymph node metastasis.
We enrolled 353 patients who received primary curative resection for EC from 1990 to 2003. The association of pN and MLR with 5-year overall survival (OS) was examined by receiver operating characteristic (ROC) and area under the curve (AUC) analysis. The Kaplan-Meier method was used to calculate survival rates, and survival curves were compared with the log-rank test. The Cox model was employed for univariate and multivariate analyses of factors associated with 5-year OS.
The median follow-up time was 41 months, and the 1-, 3- and 5-year OS rates were 71.2%, 30.4%, and 19.5%, respectively. Univariate analysis showed that age, pN stage, and the MLR were prognostic factors for OS. Patients with MLRs less than 0.15, MLRs of 0.15-0.30, and MLRs greater than 0.30 had 5-year OS rates of 30.1%, 17.8%, and 9.5%, respectively (p < 0.001). Patients classified as pN1, pN2, and pN3 had 5-year OS rates of 23.7%, 11.4%, and 9.9%, respectively (p < 0.001). Multivariate analysis indicated that a high MLR and advanced age were significant and independent risk factors for poor OS. Patients classified as pN2 had significantly worse OS than those classified as pN1 (p = 0.022), but those classified as pN3 had similar OS as those classified as pN1 (p = 0.166). ROC analysis indicated that MLR (AUC = 0.585, p = 0.016) had better predictive value than pN (AUC = 0.565, p = 0.068).
The integrated use of MLR and pN may be suitable for evaluation of OS in Chinese patients with EC and positive nodal metastasis after curative resection.
本研究旨在探讨中国食管癌（EC）伴淋巴结转移患者术后淋巴结转移（pN）数量和淋巴结转移率（MLR）与预后的关系。
纳入 1990 年至 2003 年间接受根治性切除术的 353 例 EC 患者。采用受试者工作特征（ROC）曲线和曲线下面积（AUC）分析 pN 和 MLR 与 5 年总生存率（OS）的关系。采用 Kaplan-Meier 法计算生存率，并用对数秩检验比较生存曲线。采用 Cox 模型进行单因素和多因素分析，评估与 5 年 OS 相关的因素。
中位随访时间为 41 个月，1、3 和 5 年 OS 率分别为 71.2%、30.4%和 19.5%。单因素分析显示，年龄、pN 分期和 MLR 是 OS 的预后因素。MLR<0.15、0.15-0.30 和>0.30 的患者 5 年 OS 率分别为 30.1%、17.8%和 9.5%（p<0.001）。pN1、pN2 和 pN3 患者的 5 年 OS 率分别为 23.7%、11.4%和 9.9%（p<0.001）。多因素分析表明，高 MLR 和高龄是 OS 不良的显著独立危险因素。pN2 患者的 OS 明显差于 pN1 患者（p=0.022），但 pN3 患者的 OS 与 pN1 患者相似（p=0.166）。ROC 分析表明，MLR（AUC=0.585，p=0.016）比 pN（AUC=0.565，p=0.068）具有更好的预测价值。
在根治性切除术后，MLR 和 pN 的综合应用可能适合评估中国 EC 伴阳性淋巴结转移患者的 OS。
